TWI685776B - Method of fabricating touch panel - Google Patents

Abstract

A method of forming a protective film of electrode for touch panel of this invention includes the following steps. A photosensitive layer containing a photosensitive resin composition is disposed on a substrate having electrode for touch panel, wherein the photosensitive resin composition contains a binder polymer having a carboxyl group and acid value thereof is from 30mg KOH/g to 120mg KOH/g, a photopolymerizable compound having at least three ethylenically unsaturated groups, and a photopolymerization initiator. A predetermined portion of the photosensitive layer is cured by irradiation with actinic light. A portion excepting the predetermined portion is removed, so as to form a protective film containing a cured product of the photosensitive resin composition covering a part or all of the electrodes.

Description

Manufacturing method of touch panel

The invention relates to a method for forming a protective film for electrodes of a touch panel, in particular to a method for forming a protective film suitable for protecting electrodes of a touch panel of an electrostatic capacitance method, and a photosensitive resin composition used therein Objects and photosensitive elements, and methods of manufacturing touch panels.

From large electronic devices such as personal computers or televisions to small electronic devices such as car navigation, mobile phones, and electronic dictionaries, or office automation (OA) and factory automation (FA) equipment In such display devices, liquid crystal display elements or touch panels (touch sensors) have been used. Electrodes containing transparent conductive electrode materials are provided in the liquid crystal display elements or touch panels. As a transparent conductive electrode material, indium tin oxide (Indium-Tin-Oxide, ITO), indium oxide, or tin oxide are known. These materials exhibit high visible light transmittance, and thus are used as electrodes for substrates such as liquid crystal display elements Become the mainstream.

For touch panels, various types of touch panels have been put into practical use, and in recent years, the application of electrostatic capacitive touch panels is being promoted. In an electrostatic capacitance type touch panel, if a fingertip as a conductive body contacts the touch input surface, electrostatic capacitance coupling is performed between the fingertip and the conductive film to form a capacitor. Therefore, the electrostatic capacitive touch panel detects the coordinates of the contact position by capturing the charge change at the contact position of the fingertip.

In particular, the projection type electrostatic capacitance type touch panel can realize multi-point detection of fingertips, so it has good operability for complex instructions. Due to the good operability, the following applications are being promoted. An input device on the display surface of a device with a small display device, such as a mobile phone or a portable music player.

Generally, in a touch panel of a projection type electrostatic capacitance method, in order to express the two-dimensional coordinates of the X axis and the Y axis, a plurality of X electrodes and a plurality of Y electrodes orthogonal to the X electrode form a two-layer structure as the For the electrode, Indium-Tin-Oxide (ITO) has been used.

Furthermore, the front edge area of the touch panel is an area where the touch position cannot be detected, so reducing the area of the front edge area is an important element for increasing the product value. In the frontal region, metal wiring is required to transmit the detection signal of the touch position. However, in order to reduce the frontal area, the width of the metal wiring must be narrowed. Copper is usually used for metal wiring.

However, when the touch panel as described above comes into contact with fingertips, corrosive components such as moisture or salt may enter the interior from the sensing area. If the corrosion component enters the inside of the touch panel, the metal wiring corrodes, and the resistance between the electrode and the driving circuit may increase or disconnection may occur.

In order to prevent corrosion of metal wiring, an electrostatic capacitance type projection type touch panel in which an insulating layer is formed on metal is disclosed (for example, Patent Document 1). In the touch panel, a silicon dioxide layer is formed on the metal by plasma chemical vapor growth (Chemical Vapor Deposition (CVD) method) to prevent corrosion of the metal. However, this method uses a plasma CVD method, so high temperature treatment is required and the substrate is limited. Problems such as high manufacturing costs.

In addition, as a method of providing a resist film on a necessary portion, the following method is known: a photosensitive layer containing a photosensitive resin composition is provided on a predetermined substrate, and the photosensitive layer is exposed and developed (e.g. Patent Literature 2 ~ Patent Literature 4).

Prior technical literature

Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2011-28594

Patent Document 2: Japanese Patent Laid-Open No. 7-253666

Patent Document 3: Japanese Patent Laid-Open No. 2005-99647

Patent Document 4: Japanese Patent Laid-Open No. 11-133617

The production of a protective film using a photosensitive resin composition can be expected to reduce costs compared with the plasma CVD method. However, in the case where a protective film is formed on the electrode for a touch panel, if the thickness of the protective film is large, there may be a step difference between a portion where the film is present and a portion where the film is not present. Therefore, the protective film must be made as thin as possible. However, regarding the level of 10 μm or less in thickness, there is no example in which the rust resistance of the film formed of the photosensitive resin composition is investigated.

An object of the present invention is to provide a method for forming a protective film for an electrode for a touch panel, a photosensitive resin composition and a photosensitive element capable of forming such a protective film, and a method for manufacturing a touch panel. The method for forming a protective film for a panel electrode can form a thin film but a protective film having sufficient rust resistance on a predetermined electrode for a touch panel.

In order to solve the above-mentioned problems, the present inventors conducted intensive studies and found that the photosensitive resin composition containing a specific binder polymer, a specific photopolymerizable compound, and a photopolymerization initiator has sufficient developability, and Even if the film formed by photohardening has a thickness of 10 μm or less, it exhibits sufficient rust resistance and can sufficiently prevent corrosion of metals such as copper, thereby completing the present invention.

The method for forming a protective film for an electrode for a touch panel of the present invention is characterized in that a photosensitive layer containing a photosensitive resin composition is provided on a substrate having the electrode for a touch panel, and the photosensitive resin composition contains Adhesive polymers with a carboxyl group and an acid value of 30 mg KOH/g to 120 mg KOH/g, a photopolymerizable compound with at least 3 ethylenically unsaturated groups, and a photopolymerization initiator; the predetermined part of the photosensitive layer is irradiated by irradiation After the active light is cured, the predetermined portion is removed except for a predetermined portion to form a protective film containing the cured product of the predetermined portion of the photosensitive layer covering part or all of the electrode.

According to the method for forming a protective film for an electrode for a touch panel of the present invention, by using the above-mentioned specific photosensitive resin composition, the developability and the adhesion to the substrate can be ensured, and it can be formed with a thickness of 10 μm or less. Full anti-rust protective film. According to the present invention, the photosensitive resin composition can be used to form a protective film having sufficient aesthetics and rust resistance, so that the manufacturing cost at the time of manufacturing the touch panel can be reduced.

From the viewpoint of further improving rust resistance, the above-mentioned photopolymerizable compound preferably contains at least one compound selected from the group consisting of: (a) having a skeleton derived from pentaerythritol (pentaerythritol) Group) acrylate compound, (meth)acrylate compound having a skeleton derived from dipentaerythritol, (meth)acrylate compound having a skeleton derived from trimethylolpropane, and having a skeleton derived from glycerin (Meth)acrylate compound.

From the viewpoint of sufficiently ensuring the visibility of the touch panel, the photosensitive layer preferably has a minimum visible light transmittance of 400% to 700 nm of 90% or more. In this case, it is suitable to form a protective film covering the electrodes of the sensing area.

In addition, from the viewpoint of further improving the visibility of the touch panel, the above-mentioned photosensitive layer is preferably b* in the LAB color system of the Commission Internationale de I'Eclairage (CIE) of the International Society of Illumination (CIE)- 0.2~1.0. In this case, it is suitable to form a protective film covering the electrodes of the sensing area.

Furthermore, from the viewpoint of having both developability and rust resistance, it is preferable that the photosensitive resin composition further contains at least one selected from the group consisting of triazole compounds, thiadiazole compounds, and tetrazole compounds Compound. In this case, it can have both developability and rust resistance, and a protective film having rust resistance can be formed in a good pattern.

The photopolymerization initiator preferably contains an oxime ester compound and/or a phosphine oxide compound. By containing an oxime ester compound and/or a phosphine oxide compound as a photoinitiator, even when the photosensitive layer is thin, a pattern can be formed with sufficient resolution.

In consideration of the visibility or aesthetics of the touch panel, it is desirable that the protective film has higher transparency. However, on the other hand, the inventors found that: When the photosensitive layer of the thin film with high transparency is patterned, the resolution tends to decrease. Regarding the reason, the present inventors believe that if the thickness of the photosensitive layer becomes smaller, it is easily affected by light scattering from the base material and halation occurs.

On the other hand, in the present invention, the photopolymerization initiator contains an oxime ester compound and/or a phosphine oxide compound, whereby a pattern can be formed with sufficient resolution.

Furthermore, the present inventors speculated that the reason for obtaining the above-mentioned effects is that although the oxime moiety contained in the oxime ester compound or the phosphine oxide moiety contained in the phosphine oxide compound has a relatively high photodecomposition efficiency, it also has a slight effect The appropriate threshold value is not decomposed under light leakage, so the influence of light leakage is suppressed, and as a result, the above effect can be obtained.

In the method for forming a protective film for an electrode for a touch panel of the present invention, a photosensitive element can be prepared, the photosensitive element having a support film, and a photosensitive layer provided on the support film and containing the photosensitive resin composition The photosensitive layer of the photosensitive element is transferred onto the substrate to provide the photosensitive layer. In this case, by using the photosensitive element, the roll-to-roll process can be easily realized, the solvent drying step, etc. can be shortened, which can greatly contribute to the shortening of the manufacturing step or the cost reduction.

In addition, the present invention provides a photosensitive resin composition containing a binder polymer having a carboxyl group and an acid value of 30 mg KOH/g to 120 mg KOH/g, a photopolymerizable compound having at least three ethylenically unsaturated groups, and a photopolymer A polymerization initiator, and the photosensitive resin composition is used to form a protective film for an electrode for a touch panel.

According to the photosensitive resin composition of the present invention, a protective film having sufficient anti-rust property can be formed on a predetermined touch panel electrode although it is a thin film.

From the viewpoint of sufficiently ensuring the visibility of the touch panel, the photosensitive resin composition of the present invention preferably has a minimum visible light transmittance of 90% or more when the protective film is formed.

In addition, from the viewpoint of further improving the visibility of the touch panel, the photosensitive resin composition of the present invention preferably has a b* in the CIELAB color system of -0.2 to 1.0 when the protective film is formed.

Furthermore, from the viewpoint of having both developability and rust resistance, the photosensitive resin composition of the present invention preferably further contains a group selected from the group consisting of triazole compounds, thiadiazole compounds and tetrazole compounds At least one compound in the group.

In addition, in the photosensitive resin composition of the present invention, it is preferable that the photopolymerization initiator contains an oxime ester compound and/or a phosphine oxide compound. In this case, a protective film of a thin film with high transparency can be formed in a pattern with sufficient resolution.

In addition, the present invention provides a photosensitive element including a supporting film and a photosensitive layer provided on the supporting film and containing the photosensitive resin composition of the present invention.

According to the photosensitive element of the present invention, a protective film having sufficient anti-rust property can be formed on a predetermined electrode for a touch panel although it is a thin film.

The thickness of the photosensitive layer can be set to 10 μm or less.

In addition, the present invention provides a method for manufacturing a touch panel, including The steps include: forming a part or all of the protective film covering the electrode on the substrate having the electrode for touch panel by the above-described method for forming the protective film of the present invention.

According to the present invention, a method for forming a protective film for an electrode for a touch panel, a photosensitive resin composition and a photosensitive element that can form such a protective film, and a method for manufacturing a touch panel are provided. The method for forming the protective film for the electrode for the panel can be formed on the predetermined electrode for the touch panel to form a protective film having sufficient anti-rust property even though it is a thin film.

In addition, according to the present invention, the metal electrode of the electrostatic capacitive touch panel can be protected. Furthermore, according to the present invention, the electrodes in the front edge area of the touch panel can be protected. The electrodes in the front edge area of the touch panel are formed with a metal layer such as copper that is susceptible to rust due to moisture or salt to improve Conductivity.

Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In particular, the photosensitive resin composition of the present invention is excellent in transparency and rust resistance. Therefore, as long as the purpose is to protect the electrode forming portion of the touch panel (touch sensor), regardless of the touch panel’s No matter how the composition changes, it can be used preferably. Specifically, when the structure of the touch panel is changed from a three-piece structure of a cover glass, a touch panel, and a liquid crystal panel to a cover glass integrated type and an on-cell type, as long as For the purpose of protecting the electrode formation part of the touch panel (touch sensor), it can also be preferably used.

In addition, the electrode for touch panel in this specification not only refers to the electrode located in the sensing area of the touch panel, but also includes the metal wiring in the frontal area. The electrodes provided with the protective film may be either one or both.

In addition, the term “excellent transparency” in this specification means that 90% or more of visible light of 400 nm to 700 nm is transmitted, and even if light is scattered to some extent, it is also included in the concept of transparency.

In addition, in this specification, (meth)acrylic acid means acrylic acid or methacrylic acid, (meth)acrylic acid ester means acrylate or its corresponding methacrylic acid ester, so-called (meth)acrylic acid Acyl group refers to acryl group or methacryl group. In addition, (poly)oxyethylene chain means oxyethylene group or polyoxyethylene group, and (poly)oxypropylene chain means oxypropylene group or polyoxypropylene group. Furthermore, the so-called "(EO) modification" refers to compounds with (poly)oxyethylene chains, and the so-called "(PO) modification" refers to compounds with (poly)oxypropylene chains, so-called "(EO)‧ (PO) Modification" refers to a compound having both (poly)oxyethylene chains and (poly)oxypropylene chains.

In addition, in this specification, the term "step" not only refers to an independent step, but even in a situation where it cannot be clearly distinguished from other steps, as long as the intended function of the step can be achieved, it is also included in the term. In addition, the numerical range indicated by "~" in this specification indicates a range including the numerical values described before and after "~" as the minimum value and the maximum value, respectively.

Furthermore, when the content of each component in the composition in the present specification includes multiple substances corresponding to each component in the composition, unless otherwise specified, it refers to the total of the multiple substances present in the composition the amount.

FIG. 1 is a schematic view showing an embodiment of the photosensitive element of the present invention Profile view. The photosensitive element 1 shown in FIG. 1 includes: a support film 10, a photosensitive layer 20 provided on the support film 10 and containing the photosensitive resin composition of the present invention, and the opposite to the support film 10 provided on the photosensitive layer 20侧的保护膜30。 The protective film 30 on the side.

The photosensitive element 1 of this embodiment can be preferably used to form a protective film for an electrode for a touch panel.

The support film 10 may use a polymer film. Examples of the polymer film include films including polyethylene terephthalate, polycarbonate, polyethylene, polypropylene, and polyether satin.

From the viewpoints of ensuring coverage and suppressing the reduction in resolution when the active light is irradiated through the support film 10, the thickness of the support film 10 is preferably 5 μm to 100 μm, more preferably 10 μm to 70 μm, and further preferably 15 μm to 40 μm. It is preferably 20 μm to 35 μm.

The photosensitive resin composition of the present invention constituting the photosensitive layer 20 contains a binder polymer having a carboxyl group and an acid value of 30 mg KOH/g to 120 mg KOH/g (hereinafter also referred to as (A) component), and has at least 3 ethylene properties Unsaturated photopolymerizable compound (hereinafter also referred to as (B) component) and photopolymerization initiator (hereinafter also referred to as (C) component).

In this embodiment, by combining the component (A) having an acid value within the above range and the component (B) satisfying the above conditions, the developability and the adhesion to the substrate can be ensured, and the The thickness forms a protective film with sufficient rust resistance. Therefore, according to the photosensitive resin composition of this embodiment, it is possible to form a protective film that can have both aesthetics and rust resistance.

In the case of previous photosensitive elements that take into account the film characteristics, usually over The photosensitive layer is formed with a thickness of 10 μm. To ensure the developability at this time, the acid value of the binder polymer contained in the photosensitive resin composition used is adjusted. Generally, the acid value is set to a value of about 140 mg KOH/g to 250 mg KOH/g. If such a photosensitive resin composition is used to form a protective film with a thickness of 10 μm or less on an electrode, sufficient rust resistance cannot be obtained. The present inventors speculate that the reason is that when the film is 10 μm or less, corrosive components such as moisture or salt are easily contained in the film, and this tendency is further increased by the carboxyl group contained in the binder polymer. It is considered that if the acid value is too low, it tends to be difficult to ensure sufficient developability or adhesion to the substrate. However, in the present embodiment, by combining the above-mentioned (A) component with an appropriate acid value and The above-mentioned (B) component combination that improves rust resistance can combine rust resistance and developability at a high level.

The acid value of the binder polymer as the component (A) can be measured as follows.

That is, first, 1 g of the adhesive polymer to be measured as the acid value is accurately weighed. 30 g of acetone was added to the above-mentioned accurately weighed adhesive polymer and dissolved uniformly. Then, an appropriate amount of phenolphthalein as an indicator was added to the above solution, and titration was performed using a 0.1N KOH aqueous solution. By, the acid value is calculated by the following formula.

Acid value=0.1×Vf×56.1/(Wp×I/100)

In the formula, Vf represents the titration (mL) of the KOH aqueous solution, Wp represents the measured weight (g) of the solution containing the binder polymer, and I represents the ratio of the non-volatile components in the solution containing the binder polymer measured ( quality %).

In addition, when the binder polymer is mixed with volatile components such as a synthetic solvent or a dilution solvent, it is heated in advance at a temperature higher than the boiling point of the volatile component by 10°C or more for 1 hour to 4 before accurate weighing. Hours, after removing volatile components, the acid value is measured.

In the present embodiment, the binder polymer as the component (A) is preferably a copolymer containing structural units derived from (a) (meth)acrylic acid and (b) alkyl (meth)acrylate.

(b) Examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. And hydroxyethyl (meth) acrylate.

The copolymer may further contain other monomers copolymerizable with the component (a) and/or component (b) in the structural unit.

Other monomers copolymerizable with the above-mentioned component (a) and/or (b) include, for example, tetrahydrofurfuryl (meth)acrylate, dimethylaminoethyl (meth)acrylate, (methyl ) Diethylaminoethyl acrylate, glycidyl (meth)acrylate, benzyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, (meth)acrylic acid 2, 2,3,3-Tetrafluoropropyl ester, (meth)acrylamide, (meth)acrylonitrile, diacetone (meth)acrylamide, styrene and vinyl toluene. When synthesizing the binder polymer as the component (A), the above monomers may be used alone or in combination of two or more.

The molecular weight of the binder polymer as the component (A) is not particularly limited, and from the viewpoint of coatability, coating film strength, and developability, the weight average molecular weight is usually preferably 10,000 to 200,000, more preferably 30,000 to 150,000, Excellent is 50,000~100,000. In addition, the measurement conditions of the weight average molecular weight are set to the same measurement conditions as in the examples of the present specification.

In the step of selectively removing the photosensitive resin composition layer through the development step to form a pattern, it can be developed with various known developing solutions, and when it functions as a protective film for the electrode, it increases corrosion to moisture, salt, etc. From the viewpoint of component resistance, the acid value of the binder polymer as the component (A) is set in the range of 30 mg KOH/g to 120 mg KOH/g.

In addition, by setting the acid value of the binder polymer to 30 mg KOH/g to 120 mg KOH/g, development can be performed using an alkaline aqueous solution containing water, an alkali metal salt, and a surfactant. If the acid value of the binder polymer is 30 mg KOH/g or more, sufficient developability can be obtained, and if the acid value of the binder polymer is 120 mg KOH/g or less, the resistance to corrosive components such as moisture or salt can be improved.

In addition, it is more preferable to set the acid value of the component (A) to 50 mg KOH/g to 120 mg KOH/g. If the acid value of the component (A) is within such a range, sufficient development can be obtained even when developing with an alkaline aqueous solution such as sodium carbonate, potassium carbonate, tetramethylammonium hydroxide, triethanolamine, etc. Sex. In terms of excellent developability, the acid value of the component (A) is preferably 50 mg KOH/g or more, more preferably 60 mg KOH/g or more, and still more preferably 70 mg KOH/g or more. In addition, from the viewpoint of protecting the electrodes from corrosive components such as moisture or salt when protecting the electrodes for touch panels, the acid value of the component (A) is more preferably 100 mg KOH/g or less, and particularly preferably 90 mg KOH/ g or less.

Light with at least 3 ethylenically unsaturated groups as component (B) Examples of the polymerizable compound include trimethylolpropane tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, and dipentaerythritol penta(meth)acrylate. Compounds obtained by reacting α,β-unsaturated carboxylic acids with polyols such as meth)acrylate and dipentaerythritol hexa(meth)acrylate; α,β such as trimethylolpropane triglycidyl ether triacrylate -A compound obtained by adding an unsaturated carboxylic acid to a glycidyl group-containing compound.

In terms of excellent rust resistance, the photopolymerizable compound having at least three ethylenically unsaturated groups preferably has an acid value of 5 mg KOH/g or less.

The photosensitive resin composition of this embodiment preferably contains at least one member selected from the group consisting of (meth)acrylates having a skeleton derived from pentaerythritol from the viewpoint of the suppression power of electrode corrosion and the ease of development. Compounds, (meth)acrylate compounds having a skeleton derived from dipentaerythritol, (meth)acrylate compounds having a skeleton derived from trimethylolpropane, and (meth)acrylates having a skeleton derived from glycerin The compound more preferably contains at least one selected from the group consisting of (meth)acrylate compounds having a skeleton derived from dipentaerythritol and (meth)acrylate compounds having a skeleton derived from trimethylolpropane.

Here, the (meth)acrylate having a skeleton derived from dipentaerythritol refers to an esterified product of dipentaerythritol and (meth)acrylic acid, and the esterified compound also includes an alkoxylated compound. The above-mentioned esterified compound is preferably a compound having 6 ester bonds in one molecule, or a compound having 1 to 5 ester bonds.

In addition, the above-mentioned (meth)acrylate compound having a skeleton derived from trimethylolpropane refers to an esterified product of trimethylolpropane and (meth)acrylic acid, and the esterified product also includes an alkylene oxide Radically modified compounds. The above-mentioned esterified product is preferably a compound in which the number of ester bonds in one molecule is 3, or a compound in which the number of ester bonds is 1 to 2 may be mixed.

Among the above-mentioned photopolymerizable compounds having at least three ethylenically unsaturated groups, from the viewpoint of further improving the corrosion resistance of the electrode and the ease of development, it is preferable to contain a modified one selected from alkylene oxide Hydroxymethylpropane (meth)acrylate compound, alkylene oxide modified tetramethylol methane (meth)acrylate compound, alkylene oxide modified pentaerythritol (meth)acrylate compound, alkylene oxide modified di At least one compound of pentaerythritol (meth)acrylate compound, alkylene oxide-modified glycerol (meth)acrylate compound and alkylene oxide-modified trimethylolpropane triglycidyl ether (meth)acrylate, more Preferably, it contains at least one compound selected from alkylene oxide-modified dipentaerythritol (meth)acrylate compounds and alkylene oxide-modified trimethylolpropane (meth)acrylate compounds.

As the alkylene oxide-modified tetramethylolmethane (meth)acrylate compound, for example, EO-modified pentaerythritol tetraacrylate can be used. EO modified pentaerythritol tetraacrylate is available as RP-1040 (manufactured by Nippon Kayaku Co., Ltd.).

These compounds may be used alone or in combination of two or more.

The content of the (A) component and (B) component in the photosensitive resin composition of the present embodiment is preferably 40 for the (A) component relative to 100 parts by mass of the total of the (A) component and (B) component Mass parts ~ 80 mass parts, (B) component is 20 parts by mass to 60 parts by mass, more preferably (A) component is 50 parts by mass to 70 parts by mass, (B) component is 30 parts by mass to 50 parts by mass, further preferably (A) component is 55 parts by mass to 65 parts by mass, and (B) component is 35 parts by mass to 45 parts by mass.

By setting the content of the (A) component and (B) component within the above range, sufficient coatability or film properties in the photosensitive element can be sufficiently ensured, and sufficient sensitivity can be obtained to sufficiently secure photocurability and development And the inhibition of electrode corrosion.

The photosensitive resin composition of this embodiment may contain a photopolymerizable compound other than the component (B). For the photopolymerizable compound, for example, the above-mentioned component (B) may be used in combination with one or more types of monofunctional monomers and difunctional monomers.

Examples of monofunctional monomers include: (meth)acrylic acid, alkyl (meth)acrylate exemplified as preferred monomers for synthesizing the adhesive polymer of the component (A), and copolymerizable with these Of monomers.

Examples of difunctional vinyl monomers include polyethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, polypropylene glycol di(meth)acrylate, and bisphenol A polyoxygen. Ethylene polyoxypropylene di(meth)acrylate (ie, 2,2-bis(4-propenyloxypolyethoxypolypropoxyphenyl)propane), bisphenol A diglycidyl ether di(methyl ) Acrylic esters, etc.; esterified products of polycarboxylic acids (phthalic anhydride, etc.) and substances with hydroxyl groups and ethylenically unsaturated groups (acrylic acid-β-hydroxyethyl, methacrylic acid-β-hydroxyethyl, etc.) .

When the photopolymerizable compound as the component (B) is used in combination with a monofunctional vinyl monomer or a difunctional vinyl monomer, these monomers The blending ratio of is not particularly limited, and from the viewpoint of obtaining photocurability and electrode corrosion inhibiting power, as the (B) component, it is 100 parts by mass relative to the total amount of the photopolymerizable compound contained in the photosensitive resin composition The ratio of the photopolymerizable compound is preferably 30 parts by mass or more, more preferably 50 parts by mass or more, and still more preferably 75 parts by mass or more.

Examples of the photopolymerization initiator as the component (C) include benzophenone, N,N,N',N'-tetramethyl-4,4'-diamino benzophenone (Michelinone), N,N,N',N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone Methone, 2-benzyl (benzyl)-2-dimethylamino-1-(4-morpholinylphenyl)-butanone-1, 2-methyl-1-[4-(methylthio ) Phenyl]-2-morpholinyl-acetone-1 and other aromatic ketones; benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether and other benzoin ether compounds; benzoin (benzoin), methyl benzoin, ethyl Benzoin compounds such as benzoin; 1,2-octanedione, 1-[4-(phenylthio)phenyl, 2-(O-benzoyl oxime)], ethyl ketone, 1-[9-ethyl- 6-(2-methylbenzyl)-9H-carbazol-3-yl]-,1-(O-acetyl oxime) and other oxime ester compounds; benzil dimethyl ketal (benzil dimethyl ketal) and other benzoyl derivatives; 9-phenylacridine, 1,7-bis (9,9'-acridinyl) heptanone and other acridine derivatives; N-phenylglycine and other N-benzene Glycine derivatives; coumarin compounds; oxazole compounds; phosphine oxide compounds such as 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide.

Among these, the oxime ester compound and/or the phosphine oxide compound are preferable in terms of the transparency of the formed protective film and the pattern forming ability when the film thickness is set to 10 μm or less.

In consideration of the visibility or aesthetics of the touch panel, the transparency of the protective film is preferably higher. On the other hand, the present inventors have found that when the photosensitive layer of a thin film with high transparency is patterned, the resolution tends to decrease. Regarding the reason, the present inventors believe that if the thickness of the photosensitive layer becomes smaller, it is easily affected by light scattering from the base material, causing halation. On the other hand, by containing an oxime ester compound and/or a phosphine oxide compound as (C) component, a pattern can be formed with sufficient resolution.

Furthermore, the present inventors speculated that the reason for obtaining the above-mentioned effects is that although the oxime moiety contained in the oxime ester compound or the phosphine oxide moiety contained in the phosphine oxide compound has a relatively high photodecomposition efficiency, it also has a slight effect The appropriate threshold value is not decomposed under light leakage, so the influence of light leakage is suppressed, and as a result, the above effect can be obtained.

Examples of the oxime ester compound include compounds represented by the following general formula (C-1) and general formula (C-2), and from the viewpoint of rapid curing and transparency, the following general formula (C-1) is preferred ) Represents the compound.

In the above general formula (C-1), R ¹ represents a C 1-12 alkyl group or a C 3-20 cycloalkyl group. In addition, as long as the effect of the present invention is not impaired, the aromatic ring in the general formula (C-1) may have a substituent.

In the above general formula (C-1), R ^{1 is} preferably an alkyl group having 3 to 10 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, more preferably an alkyl group having 4 to 8 carbon atoms or 4 to 4 carbon atoms. 10 cycloalkyl.

In the above general formula (C-2), R ² represents a hydrogen atom or a C 1-12 alkyl group, R ³ represents a C 1-12 alkyl group or a C 3-20 cycloalkyl group, and R ⁴ represents The alkyl group having 1 to 12 carbons, R ⁵ represents an alkyl group or aryl having 1 to 20 carbons. p1 represents an integer from 0 to 3. Furthermore, when p1 is 2 or more, a plurality of R ⁴ may be the same or different. Furthermore, carbazole may have a substituent within a range that does not impair the effects of the present invention.

In the above general formula (C-2), R ^{2 is} preferably an alkyl group having 1 to 8 carbons, more preferably an alkyl group having 1 to 4 carbons, and even more preferably ethyl.

In the above general formula (C-2), R ^{3 is} preferably an alkyl group having 1 to 8 carbon atoms or a cycloalkyl group having 4 to 15 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms or 4 to 4 carbon atoms. 10 cycloalkyl.

Examples of the compound represented by the general formula (C-1) include 1,2-octane Ketone, 1-[4-(phenylthio)phenyl, 2-(O-benzoyl oxime)], etc. Examples of the compound represented by the general formula (C-2) include ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1 -(O-acetyl oxime), etc. 1,2-octanedione, 1-[4-(phenylthio) phenyl, 2-(O-benzoyl oxime)] can be used as IRGACURE OXE 01 (BASF (BASF) (shares ) Manufacturing, trade name). In addition, ethyl ketone, 1-[9-ethyl-6-(2-methylbenzyl)-9H-carbazol-3-yl]-,1-(O-acetoyl oxime) can be used as an easy Lujia (IRGACURE) OXE 02 (manufactured by BASF Co., Ltd., trade name) is commercially available. These can be used alone or in combination of two or more.

Among the above general formula (C-1), particularly preferably 1,2-octanedione, 1-[4-(phenylthio)phenyl, 2-(O-benzoyl oxime)]. Among the above general formula (C-2), particularly preferred is ethyl ketone, 1-[9-ethyl-6-(2-methylbenzyl)-9H-carbazol-3-yl]-,1 -(O-acetyl oxime).

Examples of the phosphine oxide compound include compounds represented by the following general formula (C-3) and general formula (C-4). From the viewpoint of rapid hardening and transparency, the compound represented by the following general formula (C-3) is preferred.

In the above general formula (C-3), R ⁶ , R ⁷ and R ⁸ each independently represent an alkyl group or an aryl group having 1 to 20 carbon atoms. In the general formula (C-4), R ⁹ , R ¹⁰ and R ¹¹ each independently represent an alkyl group or an aryl group having 1 to 20 carbon atoms.

In the case where R ⁶ , R ⁷ or R ⁸ in the above general formula (C-3) is an alkyl group having 1 to 20 carbon atoms and R ⁹ , R ¹⁰ or R ¹¹ in the above general formula (C-4) is In the case of an alkyl group having 1 to 20 carbon atoms, the alkyl group may be linear, branched, or cyclic. In addition, the carbon number of the alkyl group is more preferably 5-10.

In the case where R ⁶ , R ⁷ or R ⁸ in the general formula (C-3) is an aryl group and the case where R ⁹ , R ¹⁰ or R ^{11 in} the general formula (C-4) is an aryl group, The aryl group may have a substituent. Examples of the substituent include an alkyl group having 1 to 6 carbon atoms and an alkoxy group having 1 to 4 carbon atoms.

Among these, R ⁶ , R ⁷ and R ⁸ in the general formula (C-3) are preferably aryl groups. In addition, R ⁹ , R ¹⁰ and R ^{11 in} the general formula (C-4) are preferably aryl groups.

The compound represented by the above general formula (C-3) is preferably 2,4,6-trimethyl in terms of the transparency of the formed protective film and the pattern forming ability when the film thickness is set to 10 μm or less Benzyl acetoyl-diphenyl-phosphine oxide. 2,4,6-Trimethylbenzyl-diphenyl-phosphine oxide is commercially available as, for example, LUCIRIN TPO (manufactured by BASF Corporation, trade name).

The content of the photopolymerization initiator as the (C) component is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass relative to 100 parts by mass of the total of the (A) component and (B) component. The part by mass is more preferably 2 parts by mass to 5 parts by mass.

By setting the content of the (C) component within the above range, the light sensitivity becomes sufficient, and it can be suppressed that the absorption on the surface of the composition increases when the active light is irradiated, the internal photohardening becomes insufficient, or visible light transmission Rate and other undesirable conditions.

The photosensitive resin composition of this embodiment preferably further contains a group selected from the group consisting of triazole compounds, thiadiazole compounds, and tetrazole compounds in terms of having both rust resistance and developability. At least one compound (hereinafter also referred to as (D) component).

Examples of the triazole compound include benzotriazole, 1H-benzotriazole-1-acetonitrile, benzotriazole-5-carboxylic acid, 1H-benzotriazole-1-methanol, carboxybenzotriazole, Mercapto-containing triazole compounds such as 3-mercaptotriazole, and amine-containing triazole compounds such as 3-amino-5-mercaptotriazole.

Examples of the thiadiazole compound include 2-amino-5-mercapto-1,3,4-thiadiazole, 2,1,3-benzothiadiazole, and the like.

Examples of the tetrazole compound include compounds represented by the following general formula (D-1).

R ¹¹ and R ^{12 in} the general formula (D-1) each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an amine group, a mercapto group, or a carboxymethyl group.

Examples of the alkyl group include methyl, ethyl, and propyl.

Specific examples of the tetrazole compound represented by the general formula (D-1) include, for example, 1H-tetrazole, 5-amino-1H-tetrazole, 5-methyl-1H-tetrazole, 1- Methyl-5-ethyl-tetrazole, 1-methyl-5-mercapto-tetrazole, 1-carboxymethyl-5-mercapto-tetrazole, etc.

As the component (D), a water-soluble salt of the tetrazole compound represented by the general formula (D-1) can be used. Specific examples include alkali metal salts such as sodium, potassium, and lithium of 1-carboxymethyl-5-mercapto-tetrazole.

Among these, from the viewpoints of the suppressive power of electrode corrosion, adhesion to metal electrodes, ease of development, and transparency, the component (D) is particularly preferably 1H-tetrazole, 5-amino-1H-tetrazole , 1-Methyl-5-mercapto-1H-tetrazole.

These tetrazole compounds and their water-soluble salts may be used alone or in combination of two or more.

In addition, in the case where the surface of the electrode provided with the protective film contains metals such as copper, silver, nickel, etc., from the viewpoint of further improving developability, the photosensitive resin composition preferably contains the tetrazole having an amine group in the above compound. Azole compounds. In this case, the development residue can be reduced, and the protective film can be easily formed with a good pattern. It is considered that the reason is that by disposing the tetrazole compound having an amine group, the balance between the solubility in the developing solution and the adhesion with the metal becomes good.

When the tetrazole compound having an amine group is contained, the above effects can be obtained. Therefore, the photosensitive resin composition and the photosensitive element of this embodiment are suitable for forming a protective film for protecting a metal layer such as copper to improve Protective film of electrodes in the frontal area of the conductive touch panel.

100 parts by mass relative to the total amount of (A) component and (B) component, The content of the (D) component in the photosensitive resin composition of the present embodiment is preferably set to 0.05 parts by mass to 10.0 parts by mass, more preferably set to 0.1 parts by mass to 2.0 parts by mass, and further preferably set to 0.2 parts by mass Parts ~ 1.0 parts by mass.

By setting the content of the component (D) within the above range, it is possible to sufficiently obtain the following effects: suppress defects such as developability or resolution reduction, and improve the suppression of electrode corrosion or the adhesion to the metal electrode.

In addition to this, the photosensitive resin composition of this embodiment may contain, if necessary, about 0.01 parts by mass to 20 parts by mass relative to 100 parts by mass of the total amount of the components (A) and (B). The following components: Adhesion-imparting agents such as silane coupling agents, leveling agents, plasticizers, fillers, defoamers, flame retardants, stabilizers, antioxidants, perfumes, thermal crosslinking agents, polymerization inhibitors, etc. These can be used alone or in combination of two or more.

In the photosensitive resin composition of this embodiment, the minimum value of the visible light transmittance at 400 nm to 700 nm is preferably 90% or more, more preferably 92% or more, and still more preferably 95% or more.

Here, the visible light transmittance of the photosensitive resin composition can be obtained as follows.

First, a photosensitive resin composition layer is formed by applying a coating liquid containing a photosensitive resin composition on the support film so that the thickness after drying becomes 10 μm or less and drying it. Next, a laminator was used to laminate the glass substrate so that the photosensitive resin composition layer was in contact with the glass substrate. In this way, the sample for measurement in which the photosensitive resin composition layer and the support film were laminated on the glass substrate was obtained. Then, the obtained measurement sample is irradiated with ultraviolet rays After photo-curing the photosensitive resin composition layer, the transmittance in the measurement wavelength range of 400 nm to 700 nm is measured using an ultraviolet-visible spectrophotometer.

If the transmittance of the light in the wavelength range of 400 nm to 700 nm in the normal visible wavelength range is more than 90%, for example, in the case of protecting the transparent electrode of the sensing area of the touch panel (touch sensor), Or when protecting the metal layer (such as a layer with a copper layer formed on the ITO electrode) of the front edge region of the touch panel (touch sensor), when the protective film is visible from the end of the sensing region, The image display quality, chroma, and brightness in the sensing area can be suppressed sufficiently.

In addition, from the viewpoint of further improving the visibility of the touch panel, the photosensitive resin composition of the present embodiment preferably has b* in the CIELAB color system of -0.2 to 1.0, more preferably 0.0 to 0.7, Furthermore, it is preferably 0.1 to 0.5. As in the case where the minimum value of the visible light transmittance is 90% or more, b* is preferably -0.2 to 1.0 from the viewpoint of preventing the image display quality and chromaticity of the sensing area from deteriorating. Furthermore, the measurement of b* in the CIELAB color system is obtained, for example, by using a spectrophotometer "CM-5" manufactured by Konica Minolta on a glass substrate with a thickness of 0.7 mm A photosensitive resin composition layer having a thickness of 10 μm or less was formed thereon, and after the ultraviolet ray was irradiated to cure the photosensitive resin composition layer, the light source was set to D65 and the viewing angle was 2° to measure.

The photosensitive resin composition of the present invention can be used to form a photosensitive layer on a substrate having electrodes for touch panels. For example, it is possible to prepare a coating liquid that can uniformly dissolve or disperse the photosensitive resin composition in a solvent, and apply It is spread on the substrate to form a coating film, and the solvent is removed by drying, thereby forming a photosensitive layer.

In terms of the solubility of each component, the ease of forming a coating film, and the like, the solvent may be ketone, aromatic hydrocarbon, alcohol, glycol ether, glycol alkyl ether, glycol alkyl ether acetate, ester, Diethylene glycol, chloroform, methylene chloride, etc. These solvents may be used singly or in the form of a mixed solvent containing two or more solvents.

Among the above solvents, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol dimethyl ether are preferably used. Ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, etc.

The photosensitive resin composition of this embodiment is preferably used as a photosensitive film like the photosensitive element 1 of this embodiment. By laminating a photosensitive film on the substrate 100 having electrodes for touch panels, the roll-to-roll process can be easily realized, the solvent drying step can be shortened, etc., which can greatly reduce the shortening of manufacturing steps or cost reduction contribution.

The photosensitive layer 20 of the photosensitive element 1 can be formed by preparing a coating solution containing the photosensitive resin composition of this embodiment, applying it to the support film 10 and drying it. The coating liquid can be obtained by uniformly dissolving or dispersing each component constituting the photosensitive resin composition of the present embodiment described above in a solvent.

The solvent is not particularly limited, and known solvents can be used, and examples include acetone, methyl ethyl ketone, methyl isobutyl ketone, toluene, methanol, ethanol, propanol, butanol, methylene glycol, and ethyl alcohol. Glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, Diethylene glycol diethyl ether, propylene glycol monomethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, chloroform and dichloromethane. These solvents may be used singly or in the form of a mixed solvent containing two or more solvents.

Examples of the coating method include a blade coating method, a Meyerbar coating method, a roll coating method, a screen coating method, a spin coating method, an inkjet coating method, and a spray coating method , Dip coating method, gravure coating method, curtain coating method, die coating method, etc.

The drying conditions are not particularly limited. The drying temperature is preferably set at 60°C to 130°C, and the drying time is preferably set at 30 seconds to 30 minutes.

Regarding the thickness of the photosensitive layer 20, in order to exert the effect of sufficiently protecting the electrodes such as rust resistance, and the step difference on the surface of the touch panel (touch sensor) due to the partial formation of the electrode protective film becomes extremely small The thickness of the photosensitive layer 20 is preferably 1 μm or more and 10 μm or less in terms of thickness after drying, more preferably 1 μm or more and 9 μm or less, still more preferably 1 μm or more and 8 μm or less, and still more preferably 2 μm or more and 8 μm or less, Particularly preferably, it is 3 μm or more and 8 μm or less.

In this embodiment, the photosensitive layer 20 preferably has a minimum visible light transmittance of 90% or more, more preferably 92% or more, and still more preferably 95% or more. In addition, the photosensitive layer 20 is preferably adjusted so that b* in the CIELAB color system becomes -0.2 to 1.0.

Regarding the viscosity of the photosensitive layer 20, when the photosensitive element is formed into a roll shape, the photosensitive resin composition is prevented from oozing out from the end surface of the photosensitive element 1 for a period of more than one month, and is prevented from being cut off. Sex element At 1 o'clock, when the fragments of the photosensitive resin composition adhere to the substrate and cause poor exposure or development residue when the active light is irradiated, the viscosity of the photosensitive layer 20 at 30°C is preferably 15 mPa. s~100mPa. s, more preferably 20mPa. s~90mPa. s, which is preferably 25mPa. s~80mPa. s.

In addition, the above-mentioned viscosity is the following value: A circular film with a diameter of 7 mm and a thickness of 2 mm formed of a photosensitive resin composition is used as a measurement sample, and is at 30°C and 80°C in the thickness direction of the sample When a load of 1.96×10 ^-2 N is applied, the rate of change in thickness is measured, and the rate of change is converted into a value of viscosity based on the rate of change assuming that it is Newtonian fluid.

Examples of the protective film 30 (cover film) include polyethylene, polypropylene, polyethylene terephthalate, polycarbonate, polyethylene-vinyl acetate copolymer, and polyethylene-vinyl acetate copolymer and poly Films such as laminated films of ethylene.

The thickness of the protective film 30 is preferably about 5 μm to 100 μm. From the viewpoint of storage in a roll shape, it is preferably 70 μm or less, more preferably 60 μm or less, still more preferably 50 μm or less, and particularly preferably 40 μm or less.

The photosensitive element 1 can be rolled up and stored or used.

In the present invention, a coating liquid containing the photosensitive resin composition and solvent of the present embodiment described above may be applied to a substrate having electrodes for a touch panel and dried to provide a photosensitive resin composition 'S photosensitive layer 20. In the case of this application, it is also preferable that the photosensitive layer satisfies the above-mentioned film thickness, visible light transmittance, and b* in the CIELAB color system.

Next, the method of forming the protective film for the touch panel electrode of the present invention will be described. 2(a) to 2(c) are views for explaining an embodiment of a method for forming a protective film for an electrode for a touch panel of the present invention Italian profile.

The method for forming the protective film 22 for the touch panel electrode of the present embodiment includes the following steps: In the first step, the substrate 100 having the touch panel electrode 110 and the touch panel electrode 120 is provided with The photosensitive layer 20 of the photosensitive resin composition of the present embodiment described above; the second step, hardening a predetermined portion of the photosensitive layer 20 by irradiating active light; and the third step, the predetermined layer of the photosensitive layer 20 after irradiating active light Other than the portion (the portion of the photosensitive layer that is not irradiated with active light) is removed to form a protective film 22 including a hardened product covering a predetermined portion of the photosensitive layer covering part or all of the electrode. In this way, the touch panel 200 with the protective film 22 as a touch input sheet can be obtained.

The base material 100 used in this embodiment includes substrates such as glass plates, plastic plates, and ceramic plates that are generally used as touch panels (touch sensors). An electrode for a touch panel is provided on the substrate (the electrode for a touch panel becomes an object to form a protective film). Examples of the electrode include electrodes such as ITO, Cu, Al, Mo, and TFT. In addition, an insulating layer may be provided on the substrate between the substrate and the electrode.

The substrate 100 having the touch panel electrode 110 and the touch panel electrode 120 shown in FIGS. 2(a) to 2(c) can be obtained in the following order, for example. After forming a metal film on the substrate 100 such as a PET film by sputtering in the order of ITO and Cu, a photosensitive film for etching is attached to the metal film to form a desired resist pattern, using an aqueous solution of ferric chloride, etc. After the etching solution removes unnecessary Cu, the resist pattern is stripped and removed.

In the first step of this embodiment, the sensitivity of this embodiment After the protective film 30 of the element 1 is removed, the photosensitive element 1 is heated while the photosensitive layer 20 is pressed onto the surface of the substrate 100 provided with the touch panel electrode 110 and the touch panel electrode 120, thereby Carry out transfer and lamination (refer to FIG. 2(a)).

The crimping mechanism may include a crimping roller. The pressure-bonding roller may also have a heating mechanism to allow heat-pressure bonding.

Regarding the heating temperature in the case of heating and pressure bonding, in order to sufficiently ensure the adhesion between the photosensitive layer 20 and the substrate 100 and the adhesion between the photosensitive layer 20 and the touch panel electrode 110 and the touch panel electrode 120, and The constituent components of the photosensitive layer 20 are less likely to undergo thermal hardening or thermal decomposition. The heating temperature is preferably set at 10°C to 180°C, more preferably set at 20°C to 160°C, and further preferably set at 30°C to 150°C.

In addition, with regard to the pressure at the time of heating and pressure bonding, from the viewpoint of sufficiently ensuring the adhesion between the photosensitive layer 20 and the base material 100 and suppressing the deformation of the base material 100, the pressure bonding pressure is preferably set by a linear pressure gauge 50N/m~1×10 ⁵ N/m, more preferably 2.5×10 ² N/m~5×10 ⁴ N/m, more preferably 5×10 ² N/m~4×10 ⁴ N/m.

If the photosensitive element 1 is heated as described above, it is not necessary to perform a pre-heat treatment on the substrate, but in terms of further improving the adhesion between the photosensitive layer 20 and the substrate 100, it is preferable to perform a pre-heat treatment on the substrate 100 . The preheating temperature at this time is preferably set to 30°C to 180°C.

In this embodiment, instead of using the photosensitive element 1, a coating solution containing the photosensitive resin composition and solvent of this embodiment may be prepared, and the electrode 110 for a touch panel provided on the substrate 100 may be applied. And touch surface The surface of the plate electrode 120 is dried to form the photosensitive layer 20.

The photosensitive layer 20 preferably satisfies the conditions of the film thickness, visible light transmittance, and b* in the CIELAB color system.

In the second step of the present embodiment, a predetermined portion of the photosensitive layer 20 is irradiated with active light L in a pattern through the mask 130 (see FIG. 2(b)).

When the active light is irradiated, when the support film 10 on the photosensitive layer 20 is transparent, the active light can be directly irradiated. When the support film 10 on the photosensitive layer 20 is opaque, the support film 10 is removed and the active light is irradiated. Light. In terms of protecting the photosensitive layer 20, it is preferable to use a transparent polymer film as the support film 10, and to irradiate active light through the polymer film while keeping the polymer film remaining.

As the light source for irradiating the active light L, a known active light source can be used, and examples thereof include a carbon arc lamp, an ultra-high pressure mercury lamp, a high-pressure mercury lamp, and a xenon lamp. There is no particular limitation as long as it is a light source that efficiently emits ultraviolet rays.

At this time, the irradiation amount of the active light L is usually 1×10 ² J/m ² to 1×10 ⁴ J/m ² , and the irradiation may be accompanied by heating. If the irradiation amount of the active light is less than 1×10 ² J/m ² , the photocuring effect tends to be insufficient, and if the irradiation amount of the active light exceeds 1×10 ⁴ J/m ² , there is a photosensitive layer 20 The tendency to change color.

In the third step of the present embodiment, the photosensitive layer 20 irradiated with active light is developed with a developing solution to remove the portion not irradiated with active light (ie, other than the predetermined portion of the photosensitive layer) to form a protective film 22, which protects The film 22 includes a cured part of a predetermined portion of the photosensitive layer of this embodiment that covers part or all of the electrode (see FIG. 2(c)). The formed protective film 22 may have a predetermined pattern.

In addition, after the active light is irradiated, when the support film 10 is stacked on the photosensitive layer 20, it is removed, and development is performed to remove the portion where the active light is not irradiated with a developing solution.

Examples of the development method include: using a well-known developer such as an alkaline aqueous solution, an aqueous developer, and an organic solvent, and performing development by a well-known method such as spraying, spraying, shaking immersion, scrubbing, and scraping. Among the partial removal methods and the like, it is preferable to use an alkaline aqueous solution from the viewpoint of environment and safety.

The alkaline aqueous solution is also preferably an aqueous solution of sodium carbonate. For example, a dilute solution of sodium carbonate at 20°C to 50°C (0.5% by mass to 5% by mass aqueous solution) can be preferably used.

The development temperature and time can be adjusted according to the developability of the photosensitive resin composition of this embodiment.

In addition, a surfactant, a defoamer, and a small amount of organic solvent for promoting development can be mixed in the alkaline aqueous solution.

In addition, after development, the alkali solution of the alkaline aqueous solution remaining in the photosensitive layer 20 after photo-curing may be performed by a known method such as spraying, shaking dipping, scrubbing, or scraping using an organic acid, an inorganic acid, or an acid aqueous solution of these acids Acid treatment (neutralization treatment).

Furthermore, a water washing step may be performed after acid treatment (neutralization treatment). After development, the hardened material can be further hardened by irradiating active light (for example, 5×10 ³ J/m ² to 2×10 ⁴ J/m ² ) if necessary. In addition, the photosensitive resin composition of this embodiment shows excellent adhesion to metal even without performing the heating step after development, but it may be replaced with or irradiated with active light after development if necessary Heat treatment (80℃~250℃).

As described above, the photosensitive resin composition and photosensitive element of this embodiment are suitable for forming a protective film for an electrode for a touch panel. Regarding the above-mentioned use of the photosensitive resin composition, a coating liquid mixed with a solvent can be used to form a protective film.

In addition, the present invention can provide a material for forming a protective film for an electrode for a touch panel, which contains the photosensitive resin composition of the present invention. The material for forming a protective film of the electrode for a touch panel may contain the photosensitive resin composition of the present embodiment described above, and it is preferably a coating liquid further containing the solvent.

Next, an example of the use portion of the protective film of the present invention will be described using FIGS. 3, 4 and 5. 3 is a schematic plan view showing an example of an electrostatic capacitive touch panel. The touch panel shown in FIG. 3 has a touch screen 102 for detecting the coordinates of the touch position on one surface of the transparent substrate 101, and an area for detecting the touch screen 102 is provided on the transparent substrate 101 The transparent electrode 103 and the transparent electrode 104 whose electrostatic capacitance changes. The transparent electrode 103 and the transparent electrode 104 respectively detect the X position coordinate and the Y position coordinate of the touch position.

The transparent substrate 101 is provided with an extension wiring 105 for transmitting the detection signal of the touch position from the transparent electrode 103 and the transparent electrode 104 to an external circuit. In addition, the extended wiring 105 and the transparent electrode 103 and the transparent electrode 104 are connected by the connection electrode 106 provided on the transparent electrode 103 and the transparent electrode 104. In addition, at the end of the extended wiring 105 that is connected to the transparent electrode 103 and the transparent electrode 104 on the opposite side, there is 路Connected connection terminal 107. The photosensitive resin composition of the present embodiment can be preferably used to form the protective film 122 extending from the wiring 105, the connection electrode 106, and the connection terminal 107. At this time, the electrodes located in the sensing area (touch screen 102) can also be protected at the same time. In FIG. 3, a part of the extended wiring 105, the connection electrode 106, a part of the electrode of the sensing area, and a part of the connection terminal 107 are protected by the protective film 122, but the location where the protective film is provided may be appropriately changed. For example, as shown in FIG. 4, the protective film 123 may be provided to protect the entire touch screen 102.

Using FIG. 5(a) to FIG. 5(b), the cross-sectional structure of the connection portion of the transparent electrode and the extended wiring will be described in the touch panel shown in FIG. FIGS. 5( a) to 5 (b) are partial cross-sectional views taken along the line V-V of section C shown in FIG. 3, and are diagrams for explaining the connection between the transparent electrode 104 and the extended wiring 105. As shown in FIG. 5( a ), the transparent electrode 104 and the extended wiring 105 are electrically connected via the connection electrode 106. As shown in FIG. 5( a ), a part of the transparent electrode 104 and all of the extended wiring 105 and the connection electrode 106 are covered by the protective film 122. Similarly, the transparent electrode 103 and the extended wiring 105 are electrically connected via the connection electrode 106. Furthermore, as shown in FIG. 5( b ), the transparent electrode 104 and the extension wiring 105 may be directly electrically connected. The photosensitive resin composition and the photosensitive element of this embodiment are suitable for forming the protective film of the above-mentioned structural part.

The method of manufacturing the touch panel of this embodiment will be described. First, a transparent electrode (X position coordinate) 103 is formed on the transparent electrode 101 provided on the base 100. Then, a transparent electrode (Y position coordinate) 104 is formed. The formation of the transparent electrode 103 and the transparent electrode 104 can be formed by The transparent electrode layer 103 and the transparent electrode 104 are formed by a method such as etching the transparent electrode layer on the substrate 100.

Then, on the surface of the transparent substrate 101, an extension wiring 105 for connecting to an external circuit, and a connection electrode 106 for connecting the extension wiring to the transparent electrode 103 and the transparent electrode 104 are formed. The extended wiring 105 and the connection electrode 106 may be formed after the transparent electrode 103 and the transparent electrode 104 are formed, or may be formed simultaneously when each transparent electrode is formed. Regarding the formation of the extension wiring 105 and the connection electrode 106, the extension wiring 105 and the connection electrode 106 can be formed by sputtering or the like after metal sputtering. The protruding wiring 105 can be formed using a conductive paste material containing scaly silver, for example, and formed at the same time when the connection electrode 106 is formed using a screen printing method. Then, a connection terminal 107 for connecting the extended wiring 105 to an external circuit is formed.

The photosensitive element 1 of this embodiment is crimped to cover the transparent electrode 103 and the transparent electrode 104 formed by the above steps, the extended wiring 105, the connection electrode 106, and the connection terminal 107, and a photosensitive layer is provided on the electrode 20. Then, the transferred photosensitive layer 20 is irradiated with active light L in a pattern through a photomask in a desired shape. After the active light L is irradiated, development is performed to remove other than the predetermined portion of the photosensitive layer 20, thereby forming a protective film 122 containing a cured product of the predetermined portion of the photosensitive layer 20. In this way, the touch panel with the protective film 122 can be manufactured.

Examples

Hereinafter, the present invention will be described more specifically with examples. However, the present invention is not limited to the following examples.

[Preparation of adhesive polymer solution (A1)]

Add (1) shown in Table 1 to a flask equipped with a stirrer, reflux condenser, inert gas inlet, and thermometer, and raise the temperature to 80°C under a nitrogen atmosphere, while maintaining the reaction temperature at 80°C ± 2°C. (2) shown in Table 1 was added dropwise uniformly over 4 hours. After the dropwise addition of (2), stirring was continued at 80°C±2°C for 6 hours to obtain a solution of a binder polymer having a weight average molecular weight of approximately 65,000 and an acid value of 78 mg KOH/g (solid content: 45% by mass) (A1 ).

[Preparation of adhesive polymer solution (A2)]

In the same manner as in the above (A1), a solution of a binder polymer having a weight average molecular weight of about 80,000 and an acid value of 115 mg KOH/g (solid content: 45% by mass) was obtained (A2).

[Preparation of adhesive polymer solution (A3)]

In the same manner as in (A1) above, a solution (solid content: 45% by mass) of a binder polymer having a weight average molecular weight of about 35,000 and an acid value of 156 mg KOH/g (A3) was obtained.

[Preparation of adhesive polymer solution (A4)]

In the same manner as in (A1) above, a solution (solid content: 45% by mass) of a binder polymer having a weight average molecular weight of about 45,000 and an acid value of 195 mg KOH/g (A4) was obtained.

[Preparation of adhesive polymer solution (A5)]

In the same manner as in (A1) above, a solution (solid content: 45% by mass) of a binder polymer having a weight average molecular weight of about 45,000 and an acid value of 155 mg KOH/g (A5) was obtained.

[Table 1]

In addition, the weight average molecular weight (Mw) is derived by measuring by gel permeation chromatography (Gel Permeation Chromatography, GPC) and converting using a calibration curve of standard polystyrene. The conditions of GPC are shown below.

GPC conditions

Pump: Hitachi L-6000 (manufactured by Hitachi, Ltd., product name)

Column: Gelpack GL-R420, Gelpack GL-R430, Gelpack GL-R440 (the above is manufactured by Hitachi Chemical Industry Co., Ltd., product name)

Dissolution solution: tetrahydrofuran

Measuring temperature: 40℃

Flow rate: 2.05mL/min

Detector: Hitachi L-3300 refractive index detector (Refractive Index, RI) (manufactured by Hitachi, Ltd., product name)

[Measurement method of acid value]

The acid value is measured as follows. First, the binder polymer solution was heated at 130° C. for 1 hour to remove volatile components to obtain solid components. Then, after accurately weighing 1 g of the polymer to be measured for acid value, the accurately weighed polymer was put into a Erlenmeyer flask, and 30 g of acetone was added to the polymer and dissolved uniformly. Then, an appropriate amount of phenolphthalein as an indicator was added to the solution, and titration was performed using a 0.1N KOH aqueous solution. Then, the acid value was calculated by the following formula.

Acid value=0.1×Vf×56.1/(Wp×I/100)

In the formula, Vf represents the titration amount (mL) of the KOH aqueous solution, Wp represents the weight (g) of the measured resin solution, and I represents the ratio (mass %) of nonvolatile components in the measured resin solution.

(Example 1)

[Preparation of coating liquid (V-1) containing photosensitive resin composition]

The materials shown in Table 2 were mixed for 15 minutes using a stirrer to prepare a coating liquid (V-1) containing a photosensitive resin composition for forming a protective film.

[Production of photosensitive element (E-1)]

Using a polyethylene terephthalate film with a thickness of 50 μm as a support film, and using a comma coater, the support film containing the photosensitive resin composition and the solvent prepared above is uniformly coated on the support film The cloth solution (V-1) was dried with a hot air convection dryer at 100° C. for 3 minutes to remove the solvent to form a photosensitive layer (photosensitive resin composition layer) containing a photosensitive resin composition. The thickness of the resulting photosensitive layer was 5 μm.

Then, a polyethylene film having a thickness of 25 μm was further laminated on the obtained photosensitive layer as a cover film to produce a photosensitive element (E-1).

[Measurement of Transmittance of Protective Film]

The polyethylene film, which is a cover film of the obtained photosensitive element (E-1), was peeled off on one side, and a laminator (manufactured by Hitachi Chemical Industry Co., Ltd.) was used on the glass substrate with a thickness of 1 mm so that the photosensitive layer was in contact with the glass substrate. , Trade name HLM-3000) at a roller temperature of 120°C, a substrate feed rate of 1m/min, and a crimping pressure (cylinder pressure) of 4×10 ⁵ Pa (due to the use of a thickness of 1mm, 10cm in length×10cm in width) The substrate is laminated at a linear pressure of 9.8×10 ³ N/m) to produce a laminate in which the photosensitive layer and the support film are laminated on the glass substrate.

Then, using a parallel light exposure machine (manufactured by ORC Manufacturing Co., Ltd., EXM1201), the photosensitive layer of the obtained laminate was exposed from the upper side of the photosensitive layer at an exposure amount of 5×10 ² J/m ² (i-ray ( (Measurement value at a wavelength of 365 nm) After ultraviolet irradiation, the support film was removed to obtain a transmittance measurement sample having a protective film having a thickness of 5.0 μm and containing a cured product of a photosensitive layer.

Then, using an ultraviolet-visible spectrophotometer (U-3310) manufactured by Hitachi, the visible light transmittance of the obtained sample was measured in the measurement wavelength range of 400 nm to 700 nm. The transmittance of the resulting protective film is 97% at a wavelength of 700 nm, 96% at a wavelength of 550 nm, 94% at a wavelength of 400 nm, and a minimum value of 94% at 400 nm to 700 nm, which can ensure Good transmittance.

[Measurement of b* of protective film]

The polyethylene film of the obtained photosensitive element (E-1) was peeled off on one side, and on the other hand, a laminator (manufactured by Hitachi Chemical Industry Co., Ltd.) was used on the glass substrate with a thickness of 0.7 mm so that the photosensitive layer was in contact with the glass substrate. Name HLM-3000) At a roller temperature of 120°C, a substrate feed rate of 1 m/min, and a crimping pressure (cylinder pressure) of 4×10 ⁵ Pa (due to the use of a substrate with a thickness of 1 mm, 10 cm in length×10 cm in width, Therefore, the linear pressure at this time was 9.8×10 ³ N/m), and the substrate was laminated on the glass substrate with the photosensitive layer and the support film.

Then, using a parallel light exposure machine (manufactured by ORC Manufacturing Co., Ltd., EXM1201), the resulting photosensitive layer was exposed at an amount of 5×10 ² J/m ² (i-ray (wavelength 365nm ) Under the measurement value) After irradiating ultraviolet rays, the support film is removed, and then ultraviolet rays are irradiated from above the photosensitive layer at an exposure amount of 1×10 ⁴ J/m ² (measurement value under i-rays (wavelength 365 nm)) to obtain b *Measurement sample, the b*measurement sample has a protective film with a thickness of 5.0 μm and containing the cured product of the photosensitive layer.

Then, using a spectrophotometer (CM-5) manufactured by Konica Minolta Co., Ltd., the CIELAB color system was measured on the obtained sample under the conditions of a light source setting D65 and a viewing angle of 2°. b*.

The b* of the protective film was 0.44, and it was confirmed that it had good b*.

[Salt spray test of protective film (artificial sweat resistance evaluation test)]

The polyethylene film, which is the cover film of the obtained photosensitive element (E-1), is peeled off on one side, and the polyimide film with copper sputtering (manufactured by Toray Film Processing Co., Ltd.) is sputtered in contact with the photosensitive layer. For the copper method, a laminator (manufactured by Hitachi Chemical Co., Ltd., trade name HLM-3000) is used at a roll temperature of 120°C, a substrate feed rate of 1 m/min, and a crimping pressure (cylinder pressure) of 4× 10 ⁵ Pa (Since a substrate with a thickness of 1 mm, a length of 10 cm × a width of 10 cm is used, so the linear pressure at this time is 9.8 × 10 ³ N/m), lamination is carried out. The laminate supporting the film.

Then, using a parallel light exposure machine (manufactured by ORC Manufacturing Co., Ltd., EXM1201), the photosensitive layer of the obtained laminate was exposed from the upper side of the photosensitive layer at an exposure amount of 5×10 ² J/m ² (i-ray ( (Measured value at a wavelength of 365 nm)) After irradiating ultraviolet rays, the support film was removed, and then ultraviolet rays were irradiated from above the photosensitive layer at an exposure amount of 1×10 ⁴ J/m ² (measured value at i-ray (wavelength at 365 nm)). A sample for evaluation of artificial sweat resistance was obtained. The sample for evaluation of artificial sweat resistance had a protective film containing a cured product of a photosensitive layer with a thickness of 5.0 μm.

Then, with reference to the Japanese Industrial Standards (JIS) standard (Z2371), a salt spray tester (manufactured by Suga tester (share), STP-90V2) was placed in the test tank. Under the condition of a test bath temperature of 35° C., a 50 g/L brine (pH value=6.7) was sprayed with a spray volume of 1.5 mL/h for 48 hours. After spraying, the salt water was wiped off, the surface state of the sample for evaluation was observed, and evaluation was performed according to the following rating.

A: The surface of the protective film is completely unchanged.

B: Very few traces were seen on the surface of the protective film, but copper did not change.

C: Traces are visible on the surface of the protective film, but copper has not changed.

D: There are traces on the surface of the protective film, and the copper is discolored.

The surface condition of the sample for evaluation was observed, and as a result, few traces were seen on the surface of the protective film but the copper did not change, and the evaluation was B.

[Development residue test of photosensitive layer]

The polyethylene film, which is the cover film of the obtained photosensitive element, is peeled off on one side, and the photosensitive layer is used to contact the sputtering copper on the polyimide film with copper sputtering (manufactured by Toray Film Processing Co., Ltd.). The laminator (manufactured by Hitachi Chemical Industry Co., Ltd. under the trade name HLM-3000) has a roller temperature of 120°C, a substrate feed rate of 1 m/min, and a crimping pressure (cylinder pressure) of 4×10 ⁵ Pa (because A substrate with a thickness of 1 mm and a length of 10 cm×10 cm in width was used. Therefore, the linear pressure at this time was 9.8×10 ³ N/m), and a laminated body in which a photosensitive layer and a supporting film were laminated on the sputtered copper was produced.

After producing the laminate obtained above, after storing for 24 hours under the conditions of a temperature of 23° C. and a humidity of 60%, a mask with a line/gap of 300 μm/300 μm alternately patterned by the active light transmitting section and the active light blocking section is used. Place a photomask on the support film and use a parallel light exposure machine (manufactured by ORC Manufacturing Co., Ltd., EXM1201) from the top of the mask surface with an exposure of 5×10 ² J/m ² (i-ray (wavelength 365nm The measured value under) is irradiated with ultraviolet rays in the form of an image.

Next, the supporting film laminated on the photosensitive layer was removed, and a 1.0 mass% sodium carbonate aqueous solution was used for spray development at 30°C for 40 seconds to selectively remove the photosensitive layer to form a protective film pattern. The state of the surface of the base material of the portion of the obtained substrate with a protective film pattern where the photosensitive layer was selectively removed was observed with a microscope, and the development residue was evaluated according to the following rating.

A: The surface of the substrate is completely unchanged.

B: The copper on the surface of the substrate is slightly discolored, but there is no development residue.

C: Copper on the surface of the substrate is slightly discolored, and development residue is slightly generated.

D: Development residue is generated.

The surface condition of the sample for evaluation was observed. As a result, the copper on the surface of the base material was slightly discolored, and development residue was slightly generated. The evaluation was C.

[Cross-cut adhesion test of protective film]

The polyethylene film, which is the cover film of the obtained photosensitive element, is peeled off on one side, and the photosensitive layer is used to contact the sputtering copper on the polyimide film with copper sputtering (manufactured by Toray Film Processing Co., Ltd.). The laminator (manufactured by Hitachi Chemical Industry Co., Ltd. under the trade name HLM-3000) has a roller temperature of 120°C, a substrate feed rate of 1 m/min, and a crimping pressure (cylinder pressure) of 4×10 ⁵ Pa (because A substrate with a thickness of 1 mm and a length of 10 cm × 10 cm in width is used, so the linear pressure at this time is 9.8 × 10 ³ N/m), and a laminate with a photosensitive layer and a supporting film laminated on the sputtered copper is produced .

Then, using a parallel light exposure machine (manufactured by ORC Manufacturing Co., Ltd., EXM1201), the photosensitive layer of the obtained laminate was exposed from the upper side of the photosensitive layer at an exposure amount of 5×10 ² J/m ² (i-ray ( (Measured value at a wavelength of 365 nm)) After irradiating ultraviolet rays, the support film was removed, and further ultraviolet rays were irradiated from above the photosensitive layer at an exposure amount of 1×10 ⁴ J/m ² (measured value at i-ray (wavelength at 365 nm)) A sample for a cross-cut adhesiveness test having a protective film having a thickness of 5.0 μm and containing a cured product of a photosensitive layer was obtained.

Then, referring to the JIS standard (K5400), a 100-section cross-cut test was carried out. Use a cutting knife to engrave a 1mm×1mm square grid scratch on the test surface, so that the invisible tape (Mending tape) #810 (manufactured by 3M) is strongly pressed to the grid part, and the end of the tape is After slowly peeling off at an angle of approximately 0°, observe the state of the grid and rate it according to the following rating Price cross-cutting tightness.

A: Almost 100% of the total area is in close contact.

B: In the total area, more than 95% and less than 100% of the area are in close contact.

B~C: more than 85% of the total area and less than 95% of the area are in close contact.

C: In the total area, more than 65% and less than 85% of the area remains in close contact.

C~D: more than 35% and less than 65% of the total area are in close contact.

D: The area of 0% or more and less than 35% of the total area remains in close contact.

The state of the grid of the sample for evaluation was observed, and as a result, it was a state where 95% or more of the total area on the sputtered copper was closely adhered and was evaluated as B.

(Example 2 to Example 12)

A photosensitive element was produced in the same manner as in Example 1 except that the solution containing the photosensitive resin composition and the solvent shown in Tables 3 and 4 (the units of the numerical values in the table are parts by mass) was used, and the transmittance was measured. , Salt water spray test, development residue test, cross-cut adhesion test. As shown in Table 5, in Examples 1 to 12, the measurement of transmittance, the evaluation of salt spray resistance, and the cross-cut adhesiveness were all good results.

(Comparative Example 1 to Comparative Example 8)

Except that the solution containing the photosensitive resin composition and the solvent shown in Table 6 and Table 7 (the units of the numerical values in the table are parts by mass) was used, a photosensitive element was produced in the same manner as in Example 1, and the transmittance was measured. , B* measurement, salt water spray test, development residue test, cross-cut adhesion test.

As shown in Table 8, in Comparative Example 1 and Comparative Example 2 using the binder polymer (A3) and the binder polymer (A4), the salt spray resistance (artificial sweat resistance) was poor.

In addition, ethoxylated bisphenol A dimethacrylate (BPE-500, manufactured by Shin Nakamura Chemical Industry Co., Ltd.) and polyethylene glycol #400 dimethacrylate (9G, Shin Nakamura Chemical Industry ( Co., Ltd.), and urethane diacrylate (UA-11, manufactured by Shin Nakamura Chemical Industry Co., Ltd.) as photopolymerizable compounds in Comparative Examples 3 to 6, which are also salt spray resistant Poor results.

The symbols of the components in Table 2 to Table 4, Table 6 and Table 7 indicate the following meanings

(A) Ingredients

(A1): Propylene glycol monomethyl ether/toluene solution of a copolymer with a monomer blending ratio (methacrylic acid/methyl methacrylate/ethyl acrylate=12/58/30 (mass ratio)), with a weight average molecular weight of 65,000 , Acid value is 78mg KOH/g

(A2): Propylene glycol monomethyl ether/toluene solution of a copolymer with a monomer blending ratio (methacrylic acid/methyl methacrylate/ethyl acrylate=17.5/52.5/30 (mass ratio)), with a weight average molecular weight of 80,000 , Acid value is 115mg KOH/g

Other adhesive polymers

(A3): Propylene glycol monomethyl ether of copolymer of monomer blending ratio (methacrylic acid/methyl methacrylate/butyl acrylate/butyl methacrylate=24/43.5/15/17.5 (mass ratio)) Toluene solution, weight average molecular weight 35,000, acid value 156mg KOH/g

(A4): Propylene glycol monomethyl ether/toluene solution of copolymer of monomer blending ratio (methacrylic acid/methyl methacrylate/butyl methacrylate=30/35/35 (mass ratio)), weight average molecular weight 45,000, acid value 195mg KOH/g

(A5): Propylene glycol monomethyl ether/toluene solution of a copolymer with a monomer blending ratio (methacrylic acid/methyl methacrylate/ethyl acrylate=24/46/30 (mass ratio)), with a weight average molecular weight of 45,000 , Acid value is 155mg KOH/g

(B) Ingredients

A-TMMT: Pentaerythritol tetraacrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd.)

TMPTA: Trimethylolpropane triacrylate (manufactured by Nippon Kayaku Co., Ltd.)

RP-1040: EO modified pentaerythritol tetraacrylate (manufactured by Nippon Kayaku Co., Ltd.)

DPHA: Dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.)

Other photopolymerizable compounds

BPE-500: ethoxylated bisphenol A dimethacrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd.)

9G: Polyethylene glycol #400 dimethacrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd.)

UA-11: Urethane diacrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd.)

(C) Ingredients

Yi Lujia (IRGACURE) OXE 01: 1,2-octanedione, 1-[(4-phenylthio) phenyl, 2-(O-benzoyl oxime)] (manufactured by BASF Co., Ltd.)

Yi Lujia (IRGACURE) 369: 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone-1 (manufactured by BASF Corporation)

Lucirin (Lucirin) TPO: 2,4,6-trimethylbenzyl-diphenyl-phosphine oxide (manufactured by BASF Corporation)

(D) Ingredients

1HT: 1H-tetrazole (manufactured by Toyobo Co., Ltd.)

MMT: 1-methyl-5-mercapto-1H-tetrazole (manufactured by Toyobo Co., Ltd.)

HAT: 5-amino-1H-tetrazole (manufactured by Toyobo Co., Ltd.)

3MT: 3-mercapto-triazole (manufactured by Wako Pure Chemical Industries, Ltd.)

ATT: 2-amino-5-mercapto-1,3,4-thiadiazole (manufactured by Wako Pure Chemical Industries, Ltd.)

AMT: 3-amino-5-mercaptotriazole (manufactured by Wako Pure Chemical Industries, Ltd.)

Other ingredients

Antage W-500: 2,2'-methylene-bis(4-ethyl-6-tert-butylphenol) (manufactured by Kawaguchi Chemical Co., Ltd.)

Methyl ethyl ketone: manufactured by Dongran Chemical Co., Ltd.

1‧‧‧Photosensitive element

10‧‧‧Supporting film

20‧‧‧Photosensitive layer

22, 30, 122, 123‧‧‧protective film

100‧‧‧ Base material

101‧‧‧Transparent substrate

102‧‧‧Touch screen

103‧‧‧Transparent electrode (X position coordinate)

104‧‧‧Transparent electrode (Y position coordinate)

105‧‧‧Extended wiring

106‧‧‧Connect electrode

107‧‧‧Connecting terminal

110、120‧‧‧Electrode for touch panel

130‧‧‧mask

200‧‧‧Touch panel

L‧‧‧ Active light

FIG. 1 is a schematic cross-sectional view showing an embodiment of the photosensitive element of the present invention.

2(a) to 2(c) are schematic cross-sectional views for explaining an embodiment of a method for forming a protective film for an electrode for a touch panel of the present invention.

3 is a schematic plan view showing an example of an electrostatic capacitive touch panel.

4 is a schematic plan view showing another example of an electrostatic capacitive touch panel.

FIG. 5(a) is a partial cross-sectional view taken along the line V-V of section C shown in FIG. 3, and FIG. 5(b) is a partial cross-sectional view showing another aspect.

1‧‧‧Photosensitive element

10‧‧‧Supporting film

20‧‧‧Photosensitive layer

30‧‧‧Protection film

Claims (8)

A method for manufacturing a touch panel, wherein the touch panel includes a substrate having a wiring containing copper, and a protective film covering part or all of the wiring is provided on the substrate. The manufacturing method includes: a first step, a photosensitive layer containing a photosensitive resin composition is provided on the substrate, wherein the photosensitive resin composition contains adhesive polymerization having a carboxyl group and an acid value of 30 mg KOH/g to 120 mg KOH/g Substances, photopolymerizable compounds having at least 3 ethylenically unsaturated groups, and photopolymerization initiators; and in the second step, after curing a predetermined portion of the photosensitive layer by irradiating with active light, removing the above-mentioned predetermined portion A protective film is formed, wherein the protective film includes a cured product of the predetermined portion of the photosensitive layer covering part or all of the wiring, and b* of the photosensitive layer in the CIELAB color system is 0.39 to 1.0. The method for manufacturing a touch panel as described in item 1 of the patent application range, wherein the photopolymerizable compound contains at least one compound selected from the group consisting of: (methyl having a skeleton derived from pentaerythritol ) Acrylate compound, (meth)acrylate compound having a skeleton derived from dipentaerythritol, (meth)acrylate compound having a skeleton derived from trimethylolpropane, and (methyl) having a skeleton derived from glycerol ) Acrylate compounds. The method for manufacturing a touch panel as described in item 1 or item 2 of the patent application scope, wherein The minimum value of light transmittance is more than 90%. The method for manufacturing a touch panel as described in item 1 or 2 of the patent application, wherein the photosensitive resin composition further includes 3-mercaptotriazole or 3-amino-5-mercaptotriazole. The method for manufacturing a touch panel as described in item 1 or 2 of the patent application, wherein the photosensitive resin composition further contains a group selected from the group consisting of triazole compounds, thiadiazole compounds and tetrazole compounds At least one compound. The method for manufacturing a touch panel as described in item 1 or 2 of the patent application, wherein the photopolymerization initiator contains an oxime ester compound and/or a phosphine oxide compound. The method for manufacturing a touch panel as described in item 1 or 2 of the patent application, wherein the first step includes preparing a photosensitive element, wherein the photosensitive element is provided with a support film, and is provided on the support film A photosensitive layer containing the photosensitive resin composition; and transferring the photosensitive layer of the photosensitive element onto the substrate to provide the photosensitive layer. The method for manufacturing a touch panel as described in item 1 or 2 of the patent application, wherein the thickness of the protective film is 10 μm or less.

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